According to Baidu Encyclopedia, a dual-currency card refers to a bank card issued by a domestic bank with RMB and foreign currency settlement accounts and with the logo of UnionPay and another international bank card organization. In China, the settlement network of UnionPay usually uses RMB as the settlement currency. Overseas, the settlement network of international bank card organizations designated by the dual-currency card logo can use foreign currency as the settlement currency.
There are two main types of dual-currency cards: dual-currency credit cards and dual-currency debit cards. Dual-currency credit cards are credit cards with RMB and currency settlement accounts, and their functions are basically the same as those of single-currency credit cards. Dual-currency debit cards also have RMB and USD settlement accounts, which can be used for deposit and withdrawal and consumption of RMB and USD without overdraft function.